FR3107157A1 - Thermal regulation assembly of at least one electronic component - Google Patents

Abstract

Device for thermal regulation of at least one electronic component The invention relates to an assembly (1) for thermal regulation of at least one electronic component (3) to be thermally regulated, said assembly (1) comprising a cooling device (11) through which is intended to flow a cooling fluid and a thermal interface (15) comprising at least one thermally conductive material (17) elastically deformable, configured to be interposed between the cooling device (11) and said at least one electronic component (3). According to the invention, the thermal interface (15) comprises at least one electric heating element (19). Figure for the abstract: Fig. 1

Description

Thermal regulation assembly of at least one electronic component

The present invention lies in the field of thermal regulation devices for electronic components, in particular capable of releasing heat in operation. In particular, the invention relates to the thermal regulation of such components which need to be maintained within a given temperature range in order to obtain optimum operation and lifetime. These may be electrical energy storage cells, integrated circuits, servers, data centers, or others, which require thermal regulation in order to maintain them within their operating temperature range.

The invention can be applied in particular in motor vehicles, in particular for the thermal regulation of batteries in electric or hybrid vehicles.

Data centers around the world currently represent 10% of global electricity consumption. The growth of technology for storing and transmitting information by “block chains” (Blockchain in English) and the advent of 5G telecommunications technology mean that this percentage could increase drastically in the coming years. At least half of this consumption comes from the cooling systems of these data centers. Currently the majority of data centers are air-cooled by cooling the ambient air of the storage rooms by air conditioning devices. The optimum operating temperature for data centers is between 5°C and 40°C, more specifically around 27°C.

In the automotive field, for example, it is known to implement electric batteries in the form of electronic modules capable of releasing heat in operation. Each module may comprise a plurality of electronic cells, capable of releasing heat in operation, received in a box. High density energy storage cells such as Li-ion or Li-polymer batteries ideally need to operate in a temperature range between 20°C and 40°C, and too low a temperature impacts their autonomy while too high a temperature affects their lifespan. In known manner, the various battery cells of an electrical storage system can in particular be cooled by means of a cold plate inside which a cooling fluid is intended to circulate, the plate being in contact with the cells battery to be cooled, which allows the heat from the batteries to be evacuated.

Conversely, if the surrounding temperature is too cold, the electronic components should be warmed up in order to keep them within their optimum operating temperature range.

These temperature constraints make it necessary to provide a heating device providing heat and a cooling device making it possible to capture the heat to meet the different conditions.

However, in order to optimize the thermal performance, in particular cooling, it is difficult to conceive of simply interposing a heating device between the electronic components and the cooling device comprising such as the cold plate inside which the cooling fluid.

Likewise, arranging the cooling device between a heating device and the electronic components to be thermally regulated would make the heating complicated. Indeed, in such a configuration, the heating device would have to heat the cooling device such as the cold plate and the cooling fluid it contains, even before being able to affect the electronic components to be heated.

The aim of the invention is to offer an alternative for the thermal management of at least one electronic component by at least partially overcoming the aforementioned problems of the state of the art, so as to optimize the lifespan as well as the performance of the device. such an electronic component. The invention can advantageously be used in the automotive field, for example, to thermally regulate a power electronics element or an electrical energy storage element, or even in the field of data centers to regulate servers and other electronic components.

1. un dispositif de refroidissement à travers lequel est destiné à s’écouler un fluide de refroidissement et
2. une interface thermique comportant au moins un matériau conducteur thermique déformable élastiquement, configurée pour être interposée entre le dispositif de refroidissement et ledit au moins un composant électronique.

To this end, the subject of the invention is a thermal regulation assembly of at least one electronic component to be thermally regulated, said assembly comprising:

1. a cooling device through which a cooling fluid is intended to flow and
2. a thermal interface comprising at least one elastically deformable thermal conductive material, configured to be interposed between the cooling device and said at least one electronic component.

According to the invention, the thermal interface comprises at least one electric heating element.

The thermal interface can be arranged directly in contact with said at least electronic component to be thermally regulated or with a support for the latter.

When the electrical heating element is powered, the thermal interface performs a function of heating the electronic component to be thermally regulated. The electric heating element then forms a heat source, and the thermal conductive material optimizes the heating.

On the contrary, in the absence of a power supply to the electric heating element, the thermal interface improves the conductivity and the heat transfer between the cooling device and the electronic component to be thermally regulated.

Furthermore, the cooling device forms a support for the thermal interface and is intended to maintain this thermal interface against a surface of the electronic component to be thermally regulated. The thermal interface thus fills the microporosities. When the thermal regulation assembly is mounted with the electronic component or components to be thermally regulated, for example in a battery module for a motor vehicle, no prestressing of the thermal interface is necessary, nor any specific additional support for the thermal interface.

The thermal regulation assembly may also comprise one or more of the following characteristics described below, taken separately or in combination.

According to one embodiment, the thermal interface comprises at least two layers of thermal conductive material.

Said at least one electrical heating element can be interposed between the two layers of thermally conductive material.

The two layers of thermal conductive material are advantageously identical.

Said at least one electric heating element can be bonded between the two layers of thermally conductive material.

Said at least one interposed electric heating element may be of the same length and/or width as the layers of thermally conductive material.

According to another embodiment, said at least one electric heating element is embedded inside the thermal conductive material.

Said at least one electric heating element can be placed centrally in the heat-conducting material or between the two layers of heat-conducting material.

According to one option, said at least one electric heating element comprises a resistive ink or a resistive paint. Ink or resistive paint can be loaded with carbon. The resistive ink or paint prevents the creation of an air film between the thermal conductive material and the electrical heating element.

According to another option, said at least one electric heating element comprises at least one heating wire or one heating circuit or one heating fabric.

The at least one electrical heating element includes two electrodes configured to be connected to an electrical power source.

Preferably, the heat-conducting material comprises a polymer, in particular loaded with metal or ceramic particles.

Said assembly can be configured to thermally regulate a module comprising a plurality of electronic components.

The thermal interface may comprise a plurality of electric heating elements respectively configured to be arranged in thermal contact with an associated electronic component. In particular, the thermal interface comprises at least one electrical heating element per electronic component, configured to be arranged in thermal contact with an associated electronic component.

Each electric heating element can be of the same length and/or width as an associated electronic component to be thermally regulated.

Alternatively, the thermal interface comprises at least one electrical heating element configured to be arranged in thermal contact with several electronic components.

The invention also relates to a battery module for a motor vehicle, comprising a plurality of energy storage cells, and a thermal regulation assembly as defined previously, configured to thermally regulate the energy storage cells.

Other advantages and characteristics of the invention will appear more clearly on reading the following description given by way of illustrative and non-limiting example, and the appended drawings, among which:

schematically shows a battery module for a motor vehicle integrating a thermal regulation assembly according to the invention comprising a cooling device and a thermal interface.

is a perspective view of a thermal interface according to a first embodiment comprising an electrical heating element embedded in an elastically deformable thermal conductive material.

is an exploded view of a thermal interface according to a second embodiment comprising an electrical heating element between two layers of elastically deformable thermal conductive material.

partially shows an embodiment of a heating wire of the electric heating element.

partially shows an embodiment of a heating circuit of the electric heating element.

partially shows an embodiment of a heating fabric of the electric heating element.

In these figures, identical elements bear the same reference numbers.

The following achievements are examples. Although the description refers to one or more embodiments, this does not necessarily mean that each reference is to the same embodiment, or that the features apply only to a single embodiment. Simple features of different embodiments can also be combined or interchanged to provide other embodiments.

In the description, certain elements can be indexed, such as the first element or the second element, for example. In this case, it is a simple indexing to differentiate and name elements that are close but not identical. This indexing does not imply a priority of one element over another and it is easy to interchange such denominations without departing from the scope of the present description. Nor does this indexing imply an order in time.

Referring to Figure 1, the invention relates to an assembly 1 for thermal regulation of at least one electronic component 3. It may be for example a thermal regulation assembly 1 allowing the thermal regulation of at least one electronic component 3 in the motor vehicle. The thermal regulation assembly 1 can be configured to thermally regulate a module comprising a plurality of electronic components.

In a non-exhaustive manner, the electronic component 3 to be thermally regulated can be an energy storage cell of a battery module 5 for an electric or hybrid vehicle comprising a plurality of energy storage cells. The thermal regulation assembly 1 can be arranged in a casing of such a battery module 5.

The thermal regulation concerns both the heating or the cooling of the electronic component 3.

The thermal regulation assembly 1 is intended to be arranged in thermal contact with the component 3, for example when the assembly 1 is mounted in the motor vehicle. The thermal regulation assembly 1 is advantageously intended to be arranged in direct contact with a surface of the electronic component 3 or of a support for the electronic component 3. The representation of FIG. 1 showing the thermal regulation assembly 1 underneath of the electronic component 3 is not restrictive. The thermal regulation assembly 1 can for example be arranged above the electronic component 3, or even on one side of the latter.

The thermal regulation assembly 1 is configured to provide a cooling or heating function for the electronic component 3 as required.

The thermal regulation assembly 1 comprises a cooling device 11, such as a cooling plate. A cooling fluid is intended to flow through the cooling device 11, as shown schematically by the arrows 13 in FIG. 1. To do this, the cooling device 11 forms at least in part a reservoir of the cooling fluid.

The thermal regulation assembly 1 also comprises a thermal interface 15. The thermal interface 15 is intended to be arranged in thermal contact with the electronic component(s) 3.

When the thermal regulation assembly 1 is mounted with the electronic component(s) 3 to be thermally regulated, the thermal interface 15 is interposed between the cooling device 11 and the electronic component(s) 3. The cooling device 11 forms a support of the thermal interface 15. The thermal interface 15 is thus held against a surface of the electronic component(s) 3 to be thermally regulated. No prestressing of the thermal interface 15 is necessary, nor any other specific additional support for the thermal interface 15.

The thermal interface 15 has a first face 151 intended to be arranged in thermal contact with the one or more electronic components 3 to be thermally regulated and a second face 153 intended to rest on the cooling device 11.

The thermal regulation assembly 1 can comprise a single thermal interface 15 or several thermal interfaces 15.

Figures 2 and 3 show two embodiments of the thermal interface 15.

In general, the thermal interface 15 comprises at least one thermally conductive material 17 that is elastically deformable. Such a material comprises for example a polymer. The thermal conductive material 17 is advantageously filled with metallic or ceramic particles, so as to increase the thermal conductivity. Such particles are for example “embedded” in the polymer.

The thermal conductive material 17 is advantageously also electrically insulating.

When the thermal interface 15 is pressed between the electronic component(s) 3 and the cooling device 11, the deformation of the thermal conductive material 17 makes it possible to fill in the microporosities. This guarantees the thermal contact with the electronic components 3 and makes it possible to improve the conductivity and the thermal transfer between the cooling device 1 and these electronic components 3.

According to the invention, the thermal interface 15 comprises at least one heating element 19. It is more precisely an electric heating element 19. It is intended to be powered by an electrical voltage, when a heating function is desired.

According to the illustrated embodiments, the electrical heating element 19 comprises at least one layer 21 of a heating structure or heating material. The heating structure is therefore directly integrated into the thermal interface 15.

The electrical heating element 19 is configured to be connected to at least one electrical power source. For this purpose, the electrical heating element 19 comprises two electrodes 23. The electrodes 23 are on either side of the layer 21 of heating structure. The two electrodes 23 are configured to be connected to the electrical power source. The electrodes 23 can comprise copper, carbon, graphene, graphite or any conductive polymer. The power supply can only be activated when the electronic component(s) 3 need to be warmed up.

When the electrical heating element 19 is powered, the thermal interface 15 performs a function of heating the electronic component(s) 3 to be thermally regulated. In other words, the thermal interface 15 plays an active role in the thermal regulation of the electronic components 3. The electrical heating element 19 forms a heat source, and the thermal conductive material 17 optimizes the thermal transfer.

On the contrary, in the absence of electrical power supply to the electrical heating element 19, the thermal interface 15 plays a passive role. The electrical heating element 19 does not form a heat source and therefore does not prevent cooling of the electronic components 3 if the cooling device 11 is activated. The thermal interface 15 makes it possible to improve the conductivity and the thermal transfer between the cooling device 11 and the electronic component(s) 3 to be thermally regulated.

The thermal interface 15 can comprise as many electric heating elements 19 as necessary.

According to a first embodiment shown in Figure 2, the electrical heating element 19 is embedded inside the thermal conductive material 17.

When only one electric heating element 19, it can for example be arranged centrally. It can extend over the entire width or the entire length of the thermal conductive material 17.

According to a variant embodiment not shown, several electric heating elements 19 can be embedded inside the thermally conductive material 17. Such a configuration can be provided for example, when the thermal regulation assembly is intended to thermally regulate a plurality of electronic components. In particular, the thermal interface 15 may comprise at least one electrical heating element 19 per electronic component. The electric heating elements 19 are arranged inside the thermal conductive material 17 so that on assembly with the electronic components, the various electric heating elements 19 are respectively arranged in thermal contact with an associated electronic component. Each electric heating element 19 can be of the same length and/or width as the associated electronic component.

Alternatively, the thermal interface 15 may comprise an electrical heating element 19 embedded in the thermal conductive material 17, and arranged so as to be arranged in thermal contact with several electronic components, or even all of the electronic components.

According to a second embodiment represented in FIG. 3, the thermal interface 15 is formed by a stack. This stack comprises at least two layers of thermal conductive material 17 and the electrical heating element 19. The electrical heating element 19 is arranged between the two layers of thermal conductive material 17.

The two layers of thermal conductive material 17 can be of the same length and/or of the same width and/or of the same thickness. In addition, they can be made of the same material. Preferably, the two layers of thermal conductive material 17 are identical.

A first layer of thermal conductive material 17 can form a support for the electrical heating element 19. A second layer of thermal conductive material 17 can be assembled on the electrical heating element 19 to complete the stack.

A single electric heating element 19 can be arranged between the two layers of thermal conductive material 17. This interposed electric heating element 19 can be of the same length and/or width as the two layers of thermal conductive material 17.

One or more electric heating elements 19 can be arranged between the two layers of thermal conductive material 17. The electric heating elements 19 interposed can be either of the same length or of the same width as the two layers of thermal conductive material 17, more precisely before deformation thermal conductive material 17.

One or more adhesive layers may be provided so as to bond the electric heating element or elements 19 between the two layers of thermal conductive material 17.

According to a variant not shown, the thermal interface 15 may comprise a plurality of electrical heating elements 19 arranged between the two layers of thermally conductive material 17. Such a configuration may be provided when the thermal regulation assembly is configured to thermally regulate a plurality of electronic components. The thermal interface 15 comprises for example at least one electrical heating element 19 per electronic component. The various electric heating elements 19 are arranged between the two layers of thermal conductive material 17, so as to be each in thermal contact with an associated electronic component, when the thermal regulation assembly is assembled with the electronic components. Each electric heating element can be of the same length and/or width as the associated electronic component.

Alternatively, the thermal interface 15 may comprise an electrical heating element 19 arranged between the two layers of thermally conductive material 17, so as to be in thermal contact with several electronic components, or even all of the electronic components.

Furthermore, according to one or the other of the embodiments, the electric heating element 19 can comprise a resistive ink or a resistive paint. Ink or resistive paint can be loaded with carbon. The heating structure layer 21 is in this case a support film on which the resistive ink or paint is deposited. The resistive ink or paint makes it possible to prevent the creation of a film of air between the thermal conductive material 17 and the electric heating element 19.

Alternatively, the electric heating element 19 may comprise a heating structure 21 in the form of a heating wire (FIG. 4a), or a heating circuit (FIG. 4b) or a heating fabric (FIG. 4c).

Thus, the thermal interface 15 can be heated or cooled, depending on whether the power supply to the electrical heating element 19 is activated or the cooling device 11 is activated. Depending on its temperature, the thermal interface 15 yields or absorbs heat from the component(s) 3.

In the particular case where the thermal regulation assembly 1 is intended to regulate a battery module 5 for an electric or hybrid vehicle, for example, the integration of the electrical heating element 19 into the thermal interface 15 in addition to the device cooling 11, heats the energy storage cells 3 in the event of low temperature, which is not possible with the cooling device alone. Battery temperature is better regulated, resulting in improved battery life.

Claims (10)

Assembly (1) for thermal regulation of at least one electronic component (3) to be thermally regulated, said assembly (1) comprising:

• a cooling device (11) through which a cooling fluid is intended to flow and
• a thermal interface (15) comprising at least one elastically deformable thermal conductive material (17), configured to be interposed between the cooling device (11) and said at least one electronic component (3),
  characterized in that the thermal interface (15) comprises at least one electrical heating element (19).

Assembly (1) according to Claim 1, in which the thermal interface (15) comprises at least two layers of thermally conductive material (17), and in which the said at least one electrical heating element (19) is interposed between the two layers of thermal conductive material (17). Assembly (1) according to Claim 1, in which the said at least one electrical heating element (19) is embedded inside the thermally conductive material (17). Assembly (1) according to one of Claims 1 to 3, in which the said at least one electric heating element (19) comprises a resistive ink or a resistive paint. Assembly (1) according to the preceding claim, in which the resistive ink or paint is loaded with carbon. Assembly (1) according to one of Claims 1 to 3, in which the said at least one electric heating element (19) comprises at least one heating wire or one heating circuit or one heating fabric. Assembly (1) according to one of the preceding claims, in which the said at least one electrical heating element (19) comprises two electrodes (23) configured to be connected to an electrical power source. Assembly (1) according to one of the preceding claims, in which the heat-conducting material (17) comprises a polymer. Assembly (1) according to one of Claims 1 to 8, configured to thermally regulate a module (5) comprising a plurality of electronic components (3), and in which the thermal interface (15) comprises a plurality of electrical elements (19) heated respectively configured to be arranged in thermal contact with an electronic component (3) associated. Assembly (1) according to one of Claims 1 to 8, configured to thermally regulate a module (5) comprising a plurality of electronic components (3), and in which the thermal interface (15) comprises at least one heating element ( 19) electric configured to be arranged in thermal contact with several electronic components (3).